In 2016, Brexit and the election of Donald Trump signaled a populist disruption that could have led to a political realignment in the Anglo-American world. Under this realignment, conservatives would have addressed populist sentiments by reinvigorating national sovereignty, empowering families and local communities, and restoring economic growth across the spectrum.

Doctrinaire and complacent political establishments had ignored the complaints of their populaces for too long, and now the reckoning was at hand. This reckoning seemed at first like it might benefit the parties traditionally aligned with the Right, the American Republicans and the British Conservatives.

Republicans had won unified control of the federal government, and Theresa May and the Tories seemed poised for parliamentary dominance. Now those ambitions are imperiled by policy nostalgia and flawed messaging.

Post-Brexit, Theresa May and the Conservatives seemed to have hit upon a formula that could forge an enduring majority: Say that Brexit meant Brexit, and focus on trying to put the U.K. in a promising post-Brexit condition.

While elements of Labour and the Liberal Democrats would quibble about trying to have a Brexit do-over or a watered-down Brexit, the Tories would run under the banner of a prudent one-nation conservatism and sweep all before them.

The success of Brexit neutered UKIP, the main nationalist-populist rival to the Conservatives, and May's unwavering support for implementing the national referendum — even though she'd opposed it before it passed — drew UKIP members, including those who formerly leaned Labour, into the Conservative tent. The Tory landslide in May 4's local elections, in which the party made huge inroads even in Scotland, seemed to augur great victory on June 8.

Now the Conservative government in the United Kingdom has been crippled, its hopes for a governing majority wrecked in part by its dalliance with austerity politics. The unveiling of the Conservative manifesto in the middle of May seems in many ways to have been a key inflection point.

The manifesto's most infamous provision was the so-called dementia tax, which would require the elderly to pay more for their in-home "social care" — specifically, the elderly or their estates would be liable to pay to the government any assets they had in excess of 100,000 pounds (including their homes) in order to reimburse it for the cost of care.

"Donald Trump roared into the presidency as a great outsider, a reality-TV dynamo who would scramble the political map. But the first five months of his presidency have been dominated by cookie-cutter legislative efforts, particularly on health care and taxes."

This provision was disastrous for the hopes of a Conservative realignment, driving away pro-Leave voters who used to lean Labour but would have supported a pro-Brexit Conservative party. Meanwhile, Theresa May's quick reversal on this idea and vague hedging about what might replace it damaged her standing as a strong and steady adult in the room.

In the aftermath of the manifesto's roll-out, the Conservative advantage crumbled. Prior to the manifesto, both Labour and the Conservatives were increasing their poll numbers as UKIP, SNP, and Liberal Democrat voters sorted into the bigger parties. After the manifesto, though, Conservatives stopped climbing and eventually started dropping in the polls, while Labour continued to grow. There were many other missteps, but the austerity elements of the manifesto clearly played an outsized role.

The rout of the Conservatives has implications for American politics. There are substantial differences between Donald Trump's election and Brexit (one is the election of a person, the other the passage of a measure), and there is a huge gap between the personality of the American president and that of the British prime minister. But obstacles similar to those that have tripped up the Tories now face the GOP.

President Trump cobbled together an electoral coalition premised on supplementing the conservative base (much of which voted for him in November) by an appeal to the "radical middle" — supportive of entitlements, eager for changes in trade and immigration policies, and desperate for economic growth.

On issues from financial reform to immigration to tax policy, possible areas of populist-conservative compromise beckon. For instance, targeted, pro-family tax reform could gratify social conservatives and inspire economic growth. Legislation to reverse financial consolidation could rally small-government conservatives such as Mike Lee and those Trump voters who "felt the Bern" earlier in 2016.

Even on the thorny issue of health-care reform, an effort to keep many health-care subsidies in place while adopting measures to increase the flexibility of the health-care system itself could simultaneously assuage working families' concerns about health care and encourage market-oriented innovation.

Instead of trying to create a new fusionist policy agenda for the 21st century, Republicans have too often led with a set of legislative proposals that are remarkable only for their genericness. Donald Trump roared into the presidency as a great outsider, a reality-TV dynamo who would scramble the political map. But the first five months of his presidency have been dominated by cookie-cutter legislative efforts, particularly on health care and taxes.

While the new version of the American Health Care Act is in some respects an improvement on the original bill, neither version bears a particularly Trumpian stamp. Medicaid reform and tax cuts for wealthy investors aren't exactly new policy ideas for the GOP. Much of the rest of the Republican legislative agenda has been held hostage by a desire to push through tax reform.

But the risk remains that tax reform could end up being a policy version of a Rolling Stones concert — a parade of geriatric hits — complete with calls to reduce the number of tax brackets (an issue not on the lips of most voters) and eliminate the estate tax (which is currently felt only by those who leave over $5 million to their heirs).

Tax reform is still a work in progress, so there is a chance that it could be revitalized. But policy inertia still looms. A tax-reform package that does not deliver for working families would face a harder road to passage and would represent a step backward for the project of Republican reform.

Meanwhile, the White House, rather than attempting to shepherd a targeted legislative agenda through Congress, has instead allowed itself to be consumed by internal feuds and battles with the rest of Washington. An absence of message discipline combined with an understaffed executive branch has caused the White House to dominate the headlines even as it struggles to move the political ball forward. While the administration lurches from crisis to crisis, political windows close.

This combination of policy paralysis and personality-driven polarization has dire implications for the hopes of a Republican majority in 2019 and beyond. The blue-collar voters who jumped aboard the Trump train might be willing to support cutting taxes for upper-income earners, but they are not likely to support a political party that offers only tax cuts for the wealthy (with a side of angry tweets). The middle-class voters who lean Republican because they view the GOP as the party of responsibility might be willing to overlook some coarseness on the campaign trail, but they will flee the party in droves if it offers too much scandal, controversy, and instability.

An anti-GOP tsunami could also drown the ambitions of those on the right who lean in a populist-nationalist direction. Like nature, politics abhors a vacuum, and if Republicans can't rise to the challenges of the moment, the Democrats, with a very different approach, will have their own bite at the apple.

Since 2004, American politics has been convulsed by the electorate's search for leaders who will reverse economic decline and show administrative competence. Wave election has followed wave election, and if the 2016 election was not a partisan wave, it was certainly a normative one — with Donald Trump being in some respects the polar opposite of Barack Obama's administration. Unless Republicans implement a successful policy regime, another wave could be in the offing in 2018.

Republicans might look across the aisle and the Atlantic to see what that counter-reaction might look like. Despite the millions slaughtered and hundreds of millions oppressed under the banner of socialism in the 20th century, Bernie Sanders has helped rehabilitate "socialism" in American progressive politics. Jeremy Corbyn is almost the personification of an unreconstructed leftist. A resurgent Left is likely to have little patience with a Clintonian-Blairite third way, and the empowerment of this Left could lead to results uncongenial to most members of the conservative coalition, from neoconservatives to populists.

The failure of the Tories in Britain endangers a successful Brexit, and Republicans' faltering now might threaten both limited government and the implementation of market-oriented conservatism. The old paradigms are breaking down, and the inability of the party establishments to adapt to this change led to Brexit and the ascent of Donald Trump. But there is no guarantee that right-leaning populist-nationalists will set the terms of a new political alignment. Pace Barack Obama, secular history does not have a side — it always offers choices and is full of forks. In the months ahead, those on the right will need to choose wisely.

Commentary by Fred Bauer, a writer from New England. He blogs at A Certain Enthusiasm.

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